When landscape architects Tommaso del Buono and Paul Gazerwitz were asked to create a garden for a residence being built in north London, their clients requested a "real" garden—a luxuriant and romantic outdoor space imbued with color and scent—that would provide a subtle contrast to the straight lines and strong edges of their concrete-and-wood house. Flowers, water and separate areas for sitting and eating were all part of their wish list.

Despite the limits of the site (it's approximately 2,400 square feet) and a tight budget, the architects, one of whom is a native New Yorker, have created a garden of great visual interest. Their first decision was not to plant grass but to use gravel for the pathways and limestone for the hardscape. The central and most important space in the garden is a generously propor-tioned patio adjoining one side of the house and bordered by two flower beds. To make these beds seem larger and create an informal and naturalistic space, del Buono and Gazerwitz decided to restrict their plant palette to low, billowing, bushy plants. Taking a wildflower meadow as their inspiration, they planted broad sweeps of blue-green lavender, silvery santolina, yellow-green euphorbia and spike-leafed sisyrinchium inter-spersed with iris, geranium, peonies and small bursts of intensely pink valerian.

Teak containers brought back from Antwerp and filled with delicate blue convolvulus have been placed along the side of the terrace to give additional color. A hint of formality is provided by a row of large containers holding small strawberry trees, which display their reddish yellow fruit in season.

To one side of the terrace and flowerpots is a shady corridor, bounded by a brick wall running the entire length of the garden. Along one side, Gazerwitz and del Buono planted a row of elegant pleached pear trees (pleaching involves pruning the lower branches of the tree and then braiding together the top branches to form a hedge in the air). The trees take up very little room but give structure and definition to the long space. Three diminutive rectangular pools have been cut into the gravel; stepping stones made of the same limestone as the patio seem to float on the water (children love them).

At the far end of the space, the brick wall runs along a second terrace, also paved in limestone, which serves as an out-door dining area. Here, a concrete bench that is cantilevered from a retaining wall is backed by a hedge of high boxwood and is interrupted only by a shallow reservoir that flows into a waterfall, the gentle gurgling of which adds to the atmosphere.

Thanks to careful planning, imaginative planting and a strong design sense, nothing seems cramped or small in this exuberant city garden. "Our job," says del Buono, "was to find a language that in garden terms would speak sympathetically to the house." And they succeeded.